Hi Peter
Thank you for your reply. I appreciate you taking the time to research for me. The links were a great help.
I read the cause of aortic regurgitation varies from, Congenital heart valve disease, Trauma, Rheumatic fever and Calcium deposits. Knowing his job and the conditions, poor diet, possibly drinking and smoking and stress, all could have been instrumental in the build-up of calcium deposits so there is a good chance that might be the cause of his illness. Obviously, we can never know the true answer.
Syncope relates to a lack of consciousness, so could be he had a heart attack in the hospital.
Andy